Download or read book Interaction des solutions solides mangan se cuivre avec l oxyg ne et l azote written by Jian Wen Liu and published by . This book was released on 1990 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cette these est une contribution a l'etude des cinetiques d'oxydation et de nitruration des alliages binaires mn-cu, ainsi qu'a la caracterisation des couches d'oxydes ou nitrures formes. Lors de l'oxydation, le gain de masse satisfait a une cinetique classique de type parabolique, conduisant a des energies d'activation apparentes entre 120 et 140 kj/mol, pour les alliages a 5, 10 et 36 at.%mn. Par contre, le comportement des alliages de composition voisine de 20 at.% mn est plus complexe: la cinetique d'oxydation et la nature des couches d'oxydes evoluent avec la duree et la temperature. L'identification des couches s'effectue par recoupement des resultats obtenus par analyses en diffraction des rayons x, a la microsonde et en s.d.l. Aux faibles teneurs en mn (5 et 10 at.%), ainsi que pour les temperatures inferieures a 800c (20 at.%), les couches d'oxydes se divisent en couches externes peu adherentes (cuo/cu#2o) et en une couche interne adherente (mn#3o#4/mno dispersees dans une matrice en cuivre); pour les temperatures superieures a 820c (20 at.%) et les alliages a 36 at.% mn, la couche externe est constituee de l'oxyde mixte cu#xmn#3##xo#4 et la couche interne evolue vers deux couches (mn#3o#4 et mno). Le gain de masse lie a la nitruration des alliages mn-cu est dix fois plus petit que celui relatif a l'oxydation, type cinetique n'a pas encore ete precise. Neanmoins les analyses nous permettent de conclure a la formation d'une seule couche de nitrure mixte cu#1#-#xmn#3#+#xn, de structure type perovskite

Download or read book INTERACTION DES SOLUTIONS SOLIDES MANGANESE CUIVRE AVEC L OXYGENE ET L AZOTE written by JIAN WEN.. LIU and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: CETTE THESE EST UNE CONTRIBUTION A L'ETUDE DES CINETIQUES D'OXYDATION ET DE NITRURATION DES ALLIAGES BINAIRES MN-CU, AINSI QU'A LA CARACTERISATION DES COUCHES D'OXYDES OU NITRURES FORMES. LORS DE L'OXYDATION, LE GAIN DE MASSE SATISFAIT A UNE CINETIQUE CLASSIQUE DE TYPE PARABOLIQUE, CONDUISANT A DES ENERGIES D'ACTIVATION APPARENTES ENTRE 120 ET 140 KJ/MOL, POUR LES ALLIAGES A 5, 10 ET 36 AT.%MN. PAR CONTRE, LE COMPORTEMENT DES ALLIAGES DE COMPOSITION VOISINE DE 20 AT.% MN EST PLUS COMPLEXE: LA CINETIQUE D'OXYDATION ET LA NATURE DES COUCHES D'OXYDES EVOLUENT AVEC LA DUREE ET LA TEMPERATURE. L'IDENTIFICATION DES COUCHES S'EFFECTUE PAR RECOUPEMENT DES RESULTATS OBTENUS PAR ANALYSES EN DIFFRACTION DES RAYONS X, A LA MICROSONDE ET EN S.D.L. AUX FAIBLES TENEURS EN MN (5 ET 10 AT.%), AINSI QUE POUR LES TEMPERATURES INFERIEURES A 800C (20 AT.%), LES COUCHES D'OXYDES SE DIVISENT EN COUCHES EXTERNES PEU ADHERENTES (CUO/CU#2O) ET EN UNE COUCHE INTERNE ADHERENTE (MN#3O#4/MNO DISPERSEES DANS UNE MATRICE EN CUIVRE); POUR LES TEMPERATURES SUPERIEURES A 820C (20 AT.%) ET LES ALLIAGES A 36 AT.% MN, LA COUCHE EXTERNE EST CONSTITUEE DE L'OXYDE MIXTE CU#XMN#3##XO#4 ET LA COUCHE INTERNE EVOLUE VERS DEUX COUCHES (MN#3O#4 ET MNO). LE GAIN DE MASSE LIE A LA NITRURATION DES ALLIAGES MN-CU EST DIX FOIS PLUS PETIT QUE CELUI RELATIF A L'OXYDATION, TYPE CINETIQUE N'A PAS ENCORE ETE PRECISE. NEANMOINS LES ANALYSES NOUS PERMETTENT DE CONCLURE A LA FORMATION D'UNE SEULE COUCHE DE NITRURE MIXTE CU#1#-#XMN#3#+#XN, DE STRUCTURE TYPE PEROVSKITE

Download or read book International Catalogue of Scientific Literature 1901 1914 written by and published by . This book was released on 1910 with total page 1062 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book International Catalogue of Scientific Literature written by and published by . This book was released on 1910 with total page 1066 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Uranium Ore Processing and Recovery from Non conventional Resources written by International Atomic Energy Agency and published by Agency. This book was released on 1985 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Faecal Sludge Management written by Linda Strande and published by IWA Publishing. This book was released on 2014-08-15 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is estimated that literally billions of residents in urban and peri-urban areas of Africa, Asia, and Latin America are served by onsite sanitation systems (e.g. various types of latrines and septic tanks). Until recently, the management of faecal sludge from these onsite systems has been grossly neglected, partially as a result of them being considered temporary solutions until sewer-based systems could be implemented. However, the perception of onsite or decentralized sanitation technologies for urban areas is gradually changing, and is increasingly being considered as long-term, sustainable options in urban areas, especially in low- and middle-income countries that lack sewer infrastructures. This is the first book dedicated to faecal sludge management. It compiles the current state of knowledge of the rapidly evolving field of faecal sludge management, and presents an integrated approach that includes technology, management, and planning based on Sandecs 20 years of experience in the field. Faecal Sludge Management: Systems Approach for Implementation and Operation addresses the organization of the entire faecal sludge management service chain, from the collection and transport of sludge, and the current state of knowledge of treatment options, to the final end use or disposal of treated sludge. The book also presents important factors to consider when evaluating and upscaling new treatment technology options. The book is designed for undergraduate and graduate students, and engineers and practitioners in the field who have some basic knowledge of environmental and/or wastewater engineering.

Download or read book Dictionary of Building and Civil Engineering written by Don Montague and published by Taylor & Francis. This book was released on 1996 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dual-language dictionary lists over 20,000 specialist terms in both French and English, covering architecture, building, engineering and property terms. It meets the needs of all building professionals working on projects overseas. It has been comprehensively researched and compiled to provide an invaluable reference source in an increasingly European marketplace.

Download or read book Analytical Methods in the Nuclear Fuel Cycle written by and published by . This book was released on 1972 with total page 610 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book UNESCO General History of Africa Vol I Abridged Edition written by Jacqueline Ki-Zerbo and published by Univ of California Press. This book was released on 1990 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This volume covers the period from the end of the Neolithic era to the beginning of the seventh century of our era. This lengthy period includes the civilization of Ancient Egypt, the history of Nubia, Ethiopia, North Africa and the Sahara, as well as of the other regions of the continent and its islands."--Publisher's description

Download or read book Basic Technics in Ecological Farming Techniques de Base en Agriculture Biologique Grunds tzliche Verfahren der kologischen Landwirtschaft Le Maintien de la Fertilit des Sols The Maintenance of Soil Fertility Die Erhaltung der Bodenfruchtbarkeit written by Stuart Hill and published by Birkhäuser. This book was released on 2013-12-14 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Colouring Textiles written by Agusti Nieto-Galan and published by . This book was released on 2014-01-15 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Environmental Code of Practice for Metal Mines written by Canada. Environment Canada and published by . This book was released on 2009 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes operational activities and associated environmental concerns of this industrial sector. The document applies to the complete life cycle of mining, from exploration to mine closure, and environmental management practices are recommended to mitigate the identified environmental concerns. The recommended practices in the Code include the development and implementation of environmental management tools, the management of wastewater and mining wastes, and the prevention and control of environmental releases to air, water and land. The Code of Practice will be adopted by Environment Canada and others as a guidance document that recommends environmental protection practices for the mine life cycle. The Code applies specifically to metal mines but will provide useful guidance for all sectors of the mining industry.

Download or read book Uranium Extraction Technology written by International Atomic Energy Agency and published by . This book was released on 1993 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this publication is to update and expand the first edition, which was published in 1983, and to report on later advances in uranium ore processing. It includes background information about the principles of the unit operations used in uranium ore processing and summarizes the current state of the art. Extensive references provide sources for specific technological details.

Download or read book Newer Trace Elements in Nutrition written by Walter Mertz and published by . This book was released on 1971 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Boundaries of the West African Craton written by Nasser Ennih and published by Geological Society of London. This book was released on 2008 with total page 552 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Agrochimica written by International Atomic Energy Agency and published by . This book was released on 1977 with total page 462 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organic matter and soil productivity; Turnover of plant residues; Mineralization of organic compounds; Dynamics of organic forms of nitrogen; Nitrogen economy; Biodegradation of organic matter; Biochemical transformation of organic matter; Bitumens in soil organic matter; Characterization of humic acids; Carbon dating; Modern techniques and their implact on soil organic matter research; Sludge; Soil organic matter components and plant metabolism; Interaction between agrochemicals and organic matter; Peat.

Download or read book Arsenic in Drinking Water written by National Research Council and published by National Academies Press. This book was released on 2001-11-26 with total page 241 pages. Available in PDF, EPUB and Kindle. Book excerpt: Having safe drinking water is important to all Americans. The Environmental Protection Agency's decision in the summer of 2001 to delay implementing a new, more stringent standard for the maximum allowable level for arsenic in drinking water generated a great deal of criticism and controversy. Ultimately at issue were newer data on arsenic beyond those that had been examined in a 1999 National Research Council report. EPA asked the National Research Council for an evaluation of the new data available. The committee's analyses and conclusions are presented in Arsenic in Drinking Water: 2001 Update. New epidemiological studies are critically evaluated, as are new experimental data that provide information on how and at what level arsenic in drinking water can lead to cancer. The report's findings are consistent with those of the 1999 report that found high risks of cancer at the previous federal standard of 50 parts per billion. In fact, the new report concludes that men and women who consume water containing 3 parts per billion of arsenic daily have about a 1 in 1,000 increased risk of developing bladder or lung cancer during their lifetime.